Optical screen for photographic and printing purposes.



HJS-MITH.) OPTICAL SCREEN FORy PHOTOGRAPHIO 5ND PRINTING PURPOSES.

APPLfiJATION I'ILED 22 1906.

Pat ented Mar. 2, 1909. Fly 1.

I \NVENTOR. JOHN HENR SNHTH,

I ATT R EY.

UN rE" srnrns .Ehl FFIQ II JOHN HENRY. SMITH, or ZURICH, SWITZERLAND.

' OPTICAL SCREEN FDR PHOTOGRAPHIG AND PRINTING PURPOSES.

Specification of Letters Patent.

Patented March 2,1909.

Application filed March 22, 1906. Serial No. 307,319. I

To all whom it may concern:

Be it known that I, JOHN HENRY SMITH, a subject of the King of Great Britain, residing in Zurich, in the Canton of Zurich, Republic of Switzerland, whose post-ofiice'address is No. 417 Seestrasse, Zurich, have invented certain new and useful Improvements in Optical Screens for Photographic and Print ing Purposes; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use thesame.

I have applied for patent in Germany on March 23d, 1905, application S. 20901.

The subject of the present invention is'a screen consisting of equal-sized equilateral triangular elements arranged as a plane surface to 'fit each other withoutintervening spaces or overlapping, and grouped together in definite arrangements of light and dark elements, or, in the case of colored screens, of various colored elements; the

' original elements being capable of arranging into elements .of higher order, and these again into groups of light and dark or colored elements. In this variety in the grouping of the elements lies the possibility of obtaining the most favorable disposition of the contrasting-elements.

Under the designation color screen it is to beunderstood that not only such screens are intended in which all the unit elements are colored in variably contrasting colors but such as contain in addition tothe colored elements'also colorless or white or black or gray elements or mixtures of such colorless and neutral tinted elements. a 1

In the accompanying drawing a few examples of. the screen on an enlarged scale are shown. I

Figure 1' shows a screen area answering to. the general description; Fig. 2 shows at (a) the grouping of 6 triangular elements to form the screened area; Fig. 3 shows a screen composed of hexagonal elements colored in. three contrasting colors; Fig. 4 shows a hexagonal screen in which the similar colors have been imprinted upon 2- printed surface (shew-n as black elements), thus yielding one or t ree color hotography, as it enables me to distribute tl ie three primary colors absoe lutely evenly without linear structure. Fig. 3 shows such a screen, B indicating the blue, G the green, and R the red elements.

'The color screens may be upon some transparent base as glass, etc., and serveas-taking or viewin screens in the process of color photography; or u on an opaque base as parints by the subsequent. application of a lilank printing similarly screened block. What I claim is: i 7

1. As a new article of manufacture, a color screen for photographic and" rinting poses, having equal-sized, e u ateraltriangular unit elements groupe definite arrangement without overlapping and without intervening spaces.

screen for photographic and rinting purposes, having equal-sizedequ' ateral triangular unit elements arranged in hexagonal groups, which are in turn grouped together ping and without intervening spaces.

3. As a new article of manufacture, a color screen for photographic and rinting purposes, having equal-sized equilateral triangroups and which groups are in turn grouped together in a definite arrangement of contrasting color areas without overlapping and without intervening spaces.

triangles into hexagons, and the circular rou ing of these again 18 of great importance per to serve fort e-production of colored together in a gular unit elements arranged in hexagonalcomponent of the colored screen as shown in pur- . 2. As a new article of manufacture, a color .in a definite arrangement without overlap- 4. As anew article of manufacture, a color In testimony Whereof,- I have signed my screen for photographic and printing urname to this specification in the presence of 10 poses, having equal-sized equilateral tnanv two subscribing witnesses. v

gular unit elements arranged in hexagonal JOHN HENRY SMITH groups, the hexagonal elements meetingl around each central point being colored in i Witnesses: three definite contrasting colors, and Without HERMANN HUBER, overlapplng and Without intervening spaces. 1 A. LIEBERKNEGHT. 

